Network component for an optical network comprising an emergency operation function, especially for an optical network in ring topology

ABSTRACT

A network component ( 3   d ) for an optical network ( 1 ) is described, including a coupling device ( 2; 4, 5 ) for optical coupling of the network component ( 3   d ) to the optical network ( 1 ), the coupling device ( 2; 4, 5 ) having a receiving module ( 4 ) and a transmitting module ( 5 ); a first data processing device ( 8, 9 ) which is unidirectionally connected to the receiving module ( 4 ); a second data processing device ( 10, 11 ) which is unidirectionally connected to the transmitting module ( 5 ); the first data processing device ( 8, 9 ) being unidirectionally connected to the second data processing device ( 10, 11 ) for transmitting data to the second data processing device; a detection device ( 4 ) for detecting the network status; and a two-way switch ( 23 ) for switching of the input of the first data processing device ( 8, 9 ) between the receiving module ( 4 ) and the output ( 19 ) of the second data processing device ( 10, 11 ) as a function of the network status detected.

BACKGROUND INFORMATION

[0001] The present invention relates to a network component for anoptical network including an emergency running function, in particularfor a network based on ring topology.

[0002] Multimedia systems in contemporary motor vehicles are designed asnetwork systems which utilize optical or electrical bus systems based onring topology. Key components (e.g., a control unit) whose internalstructures are made up by a plurality of individual components (e.g.,man-machine-interface-processor, tuner, gateway, etc.) may beinterconnected in such a ring topology. For reasons of bus conformity,the mounting of these components in a housing requires a message anddata exchange via the external bus, i.e., an internal data exchangebetween individual components which are independent of one another isnot permissible. The components combined within one device act outwardlylike separate logical devices.

[0003] If, in such a configuration, an internal gateway is connected tothe interior CAN of the vehicle, e.g., via the CAN bus, then the relayof CAN messages to the internal components of the device and thecommunication between the components cease to take place in the event offailure of the external optical ring. Interruption of the ring thuscauses complete failure of the system.

[0004]FIG. 2 shows the design of a known multimedia system for motorvehicles including an optical bus system 1 in the form of ring topology.D2B, MOST, or similar systems may be used here as bus systems common inmotor vehicles. Additional components 3 a through 3 d are integratedinto this optical ring.

[0005] A specific component 3 d, explained here in greater detail, isoptically coupled to optical bus system 1 via a connector system 2 whichin turn is composed of a receiving module 4 and a transmitting module 5.Receiving module 4 receives optical signals from optical bus system 1and converts them into electrical signals. Electrical signals areconverted into optical signals in transmitting module 5 and are fed intoring 1.

[0006] The internal structure of interconnected component 3 d havingindependent individual components 6 and 7 is schematically illustratedin FIG. 1. Component 6 has a transceiver 8 and a processor 9. Inaddition to transceiver 10 and processor 11 component 7 has anadditional interface for exchanging data and commands with other commonbus systems in the motor vehicle via lines CAN_H and CAN_L, implementedhere as CAN bus interface 12, which is connected to processor 11 via busB3. Line 22 is connected to an output STATUS of connector system 2 andsignals activity (light) on optical ring 1 to processors 9 and 11 ofinternal components 6 and 7.

[0007] Optical signals from ring 1 are available as electrical signalsat output RX_DATA of receiving module 4 on line 13 and are relayed toinput 15 of transceiver 8 of component 6.

[0008] Using transceiver 8, processor 9 may pick up data and commandsfrom the ring via bus B1 and feed them into input 18 of transceiver 10via output 16 of transceiver 8 and line 17. Using transceiver 10, thedata exchange from processor 11 takes place via bus B2, processor 11feeding its data into input TX_DATA of the transmitting module viaoutput 19 of transceiver 10 and line 21. Data and commands are availableon ring 1 after electrical/optical conversion in transmitting module 5.

[0009] It is apparent in FIG. 2 that an electrical ring, composed ofline 13, transceiver 8, line 17, transceiver 10, line 21, and connectorsystem 2, exists after optical/electrical conversion by receiving module4 and electrical/optical conversion by transmitting module 5 insidecomponent 3 d.

[0010] If processor 11 receives data, which is intended for processor 9,via CAN interface 12 or if data exchange between processors 9 and 11 isto occur, this may only take place via optical ring 1, line 13,transceiver 8, line 17, transceiver 10, and line 21. The coupling pointbetween the optical bus system and the electrical ring is formed byconnector system 2. Data exchange between the internal components of thedevice ceases to take place if optical bus system 1 is interrupted orconnector system 2 has faulty contacts. This results in complete failureof the device, even if the device could also be operated inside thedevice or via other motor vehicle-specific interfaces (e.g., CANinterface 12) without additional nodes from optical bus 1.

[0011] The object of the present invention is to design a networkcomponent for an optical network including an emergency runningfunction, in particular for an optical network based on ring topology,which ensures minimum emergency running properties (e.g., usability bythe driver, error indicator, acoustic warning signals, maintenance ofminimum (radio) functions) within the component in the event ofinterruption of the optical or electrical ring.

ADVANTAGES OF THE INVENTION

[0012] The network component for an optical network including anemergency running function according to the present invention, inparticular for an optical network based on ring topology, having thefeatures of claim 1 has the following advantages:

[0013] no further internal device interfaces are required for theemergency running property mentioned above;

[0014] no additional message catalog is required;

[0015] due to the electrical interconnection of the components withinthe network component, full performance capacity of the same softwaremay be used during emergency and normal operation;

[0016] this concept is expandable to the desired extent within thenetwork component. Any number of additional components may beinterconnected at the linkage point between the first and second dataprocessing devices.

[0017] The idea on which the present invention is based is to maintainan emergency running property of different key components within thenetwork component by having these key components interconnected in aminimum ring system. The full functionality of the network component maythen be utilized, less the functions which are made available on theoptical ring by other bus nodes.

[0018] Advantageous refinements of and improvements on the emergencyrunning circuit for an optical network based on ring topology, mentionedin claim 1, are found in the subclaims.

[0019] According to a preferred refinement, the coupling device includesan optical connector system.

[0020] According to a further preferred refinement, the receiving moduleincludes the detection device for detecting the network status andoutputs a logical electrical signal of at least one bit corresponding tothe respective active/non-active network status.

[0021] According to a further preferred refinement, the first dataprocessing device and/or the second data processing device are connectedto the detection device.

[0022] According to a further preferred refinement, the first dataprocessing device and/or the second data processing device each have atransceiver and a processor connected to it.

[0023] According to a further preferred refinement, the switchoverdevice receives the logical electrical signal as a control signal and,if the network is active, connects the input of the first dataprocessing device to the receiving module and, if the network is notactive, connects the input of the first data processing device to theoutput of the second data processing device.

[0024] According to a further preferred refinement, the first dataprocessing device and/or the second data processing device are connectedto a wire-bound network via an interface.

[0025] According to a further preferred refinement, a missing logicalelectrical signal is output as a fault message by the first dataprocessing device and/or the second data processing device on a displayor via the interface after transmitting its own message to indicate anactive network status.

DRAWING

[0026] An exemplary embodiment of the present invention is illustratedin the drawing and is explained in greater detail in the followingdescription.

[0027]FIG. 1 shows the structure of a multimedia system for motorvehicles including an emergency running property according to oneembodiment of the present invention; and

[0028]FIG. 2 shows the structure of a known multimedia system for motorvehicles.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0029]FIG. 1 shows the structure of a multimedia system for motorvehicles including an emergency running property according to anembodiment of the present invention. The same reference numbers in FIG.1 indicate the same components or components having the same functionsas in FIG. 1.

[0030] In this embodiment, a switchover device 23 for ensuring emergencyrunning properties is inserted according to FIG. 1. Switchover device 23is connected to output RX_DATA of connector system 3 via its input IN1and line 13. Second input IN2 of switchover device 23 is in contact withline 21 and is thus connected to output TX_DATA of connector system 3.Output OUT of switchover device 23 is connected to input 15 oftransceiver 8 via line 28. Input EN′ of switchover device 23 isconnected to line 22.

[0031] Switchover device 23 is structured so that its output OUT isconnected to one of the inputs IN1 or IN2 as a function of the signalvoltage at input EN′. The potential at EN′ in FIG. 1 is selected suchthat at potential zero input IN1 is connected to output OUT, i.e., atpotential 1 input IN2 is connected to output OUT.

[0032] According to the application, the potential at EN′ may bereversed by the selection of an appropriate switch or suitable switchingactions.

[0033] In the idle state of the device configuration illustrated in FIG.1 there is no light on optical ring 1 and potential 1 is applied to EN′of two-way switch 23 via line 22. Input IN2 is connected to output OUT.A signal transmitted from processor 9 via bus B1 reaches input 18 oftransceiver 10 via output 16 of transceiver 8 and line 17. The signal isrelayed from here to input TX_DATA of connector system 3 via output 19of transceiver 10 and line 21. After electrical/optical conversion intransmitting module 5, the signal transmitted from processor 9 isapplied to optical ring 1 which thus enters the active state.

[0034] Bus activity is signaled to processors 9 and 11 via zeropotential on line 22 connected to input EN′ of two-way switch 23 whichconnects input IN1 to output OUT due to the potential change. Afteroptical/electrical conversion in receiving module 4, the signals fromoptical ring 1 reach input IN1 of two-way switch 23 via output RX_DATAof receiving module 4 and line 13, output OUT of two-way switch 23 beingconnected to input 15 of transceiver 8 via line 28.

[0035] The bus buildup is completed: External components 3 a through 3 cand components 6 and 7 within the device may exchange data among eachother.

[0036] Interruption of optical ring 1 or faulty connections at connectorsystem 2 result in the complete failure of the entire bus system. In thepresent embodiment this is circumvented within the device due to thefact that in the event of such a fault, line 22, due to the missingstatus “bus active,” continues to carry potential 1. Therefore, two-wayswitch 23 continues to connect input IN2 to output OUT and closes anelectrical ring within the device via line 28, transceiver 8, line 17,transceiver 10, and line 21. The communication between the componentswithin the device thus persists and communication with devices connectedto this bus system may take place via an interface normally used inmotor vehicles, e.g., CAN interface 12.

[0037] After transmitting its own message, processors 9 and 11 mayindicate or output this error by the missing status message of line 22,e.g., on a display or via CAN interface 12.

[0038] Although the present invention has been described above on thebasis of a preferred exemplary embodiment, it is not limited to it, butit is rather modifiable in many ways.

[0039] In particular, the detection of the network status according tothe above embodiment is only exemplary and could also be performed byone of the processors, for example.

What is claimed is:
 1. A network component (3 d) for an optical network(1), in particular for an optical network (1) based on ring topology,comprising: a coupling device (2; 4, 5) for optically coupling thenetwork component (3 d) to the optical network (1), the coupling device(2; 4, 5) having a receiving module (4) for the conversion of opticalnetwork data into electrical data and a transmitting module (5) for theconversion of electrical data into optical network data; a first dataprocessing device (8, 9) which is unidirectionally connected to thereceiving module (4) for receiving electrical data from receiving module(4); a second data processing device (10, 11) which is unidirectionallyconnected to the transmitting module (5) for transmitting electricaldata to the transmitting module (5); the first data processing device(8, 9) being unidirectionally connected to the second data processingdevice (10, 11) for transmitting data to the second data processingdevice (10, 11); a detection device (4) for detecting the networkstatus; and a two-way switch (23) for switching the input of the firstdata processing device (8, 9) between the receiving module (4) and theoutput (19) of the second data processing device (10, 11) as a functionof the network status detected.
 2. The network component (3 d) asrecited in claim 1, wherein the coupling device (2; 4, 5) includes anoptical connector system (4, 5).
 3. The network component (3 d) asrecited in claim 1 or 2, wherein the receiving module (4) includes thedetection device for detecting the network status and outputs a logicalelectrical signal (STATUS) of at least one bit corresponding to theparticular active/non-active network status.
 4. The network component (3d) as recited in claim 1, 2 or 3, wherein the first data processingdevice (8, 9) and/or the second data processing device (10, 11) areconnected to the detection device (4).
 5. The network component (3 d) asrecited in one of the preceding claims, wherein the first dataprocessing device (8, 9) and/or the second data processing device (10,11) include a respective transceiver (8; 10) and a processor (9; 11)connected thereto.
 6. The network component (3 d) as recited in one ofthe preceding claims 3 through 5, wherein the two-way switch (23)receives the logical electrical signal (STATUS) as a control signal andconnects the input of the first data processing device (8, 9) to thereceiving module (4) if the network status is active and connects theinput of the first data processing device (8, 9) to the output (19) ofthe second data processing device (10, 11) if the network status isnon-active.
 7. The network component (3 d) as recited in one of thepreceding claims, wherein the second data processing device (10, 11) isconnected to a wire-bound network via an interface (12).
 8. The networkcomponent as recited in claim 7, wherein a missing logical electricalsignal (STATUS) for indicating an active network status is indicated ona display or output via the interface (12) as an error message by thefirst data processing device (8, 9) and/or the second data processingdevice (10, 11) after transmitting its own message.